1. Field of the Invention
The present invention relates to wake on local area network signaling to a physical host in a multi-root virtualization environment.
2. Background of the Related Art
Many computer systems now have a remote power on function, such as Wake on LAN (Local Area Network) (WOL) technology. WOL is the ability to power on remote computers through the use of special network packets. WOL is based on the principle that when the PC shuts down, the network interface card or LAN adapter still receives power and keeps listening on the network for a special WOL packet to arrive. When the WOL packet is received, the network interface card sends an out-of-band signal to the power supply, which then supplies electrical power to the rest of the computer. Unfortunately, WOL only works with network cards and motherboards that are WOL compliant and is only capable of powering on the entire computer through the power supply.
In a multi-root I/O virtualization environment, a single network interface card services multiple physical hosts. However, there is no defined mechanism for the shared network interface card to signal which physical host should be awakened by the receipt of the network packet. Even though the network packet itself will contain the media access control (MAC) address associated with the physical host to be awakened, the current out of band signaling is done with a single WAKE signal line from the I/O device.